الفهرس 
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Abstract
The aim of the present work is to study the possibility of producing
basic low hydrogen electrodes using, whenever possible, local raw
materials. For this purpose, a wide range of different electrode coverings
of basicity index between 1.8 and 3.39 have been proposed. The production
of electrodes was carried out first on a small scale, I kg production unit,
then on a larger scale of 100Kg. Accordingly, optimum production
conditions; ingredient size distribution, the extrusion aids, dry and wet
mixing times, the binder addition, and the drying processes, have been
determined.
So far successfully produced electrodes were tested to determine the
welding properties, such as arc stability, bead appearance and electrode
spattering. In this respect, each flux ingredient content limitation range has
been carefully determined and the electrodes with non-acceptable,
properties were excluded.
Moreover, standard welding tests according to Lloyd’s Register of
Shipping and American Bureau of Shipping were carried out for the five
successfully produced electrode types. The hydrogen content of the weld
deposits was in the range 1.9 to 5.8 c.c./ 100 gm from which the electrodes
could be classified as extra low hydrogen types.
On the basis of chemical anaylsis of weld deposits, uncompletely
verified theory{70.88,126j for slag-metal reactions during welding was
extended and found to be applicabl on present results. The theory was
verified for the Mn and Si transfer during multipass welding process in the
presence of alloy fluxes. The efficiency of alloying additions transfer for the
present low hydrogen basic electrodes was correlated with the atomic
percent of the alloying element in the flux metallic phase:
1JMn = 77.4 - 1.15 [Mn at %]Flux
1JSi = 55.2 - 0.64 [Si at%] Flux
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Besides, analysis of the present mechanical properties, tensile
properties and hardness were found to conform with the existing
regression equations which relate mechanical and chemical composition,
Mn & Si . However, it was necessary to develop a formula in order to
account for the present impact results:
Cv = 282
144.1 (Mn - 0.323 Si), J
The tensile properties, hardness and impact values of the present weld
deposits were conformed with the values recommended by the Lloyd’s
Register of Shipping and American Bureau of Shipping.
Present results were used to develop a procedure for the low hydrogen
electrode design, which was proved to realize the recommended chemical
composition and mechanical properties of weld zones.